Golf putting practice device

ABSTRACT

A wheel-shaped device having a dimpled peripheral surface, and a diameter and weight corresponding to that of a U.S.G.A. approved golf ball. About 75 percent of the weight is concentrated in a heavy metal cylinder having approximately a one-half inch diameter and axially distributed near the central portion of the device. The object is to provide an exaggerated off-target directional motion of the device when it is struck by a golf putter club at an improper angle. Lightweight spherical dimpled elements may be attached to opposite sides of the device to produce the appearance of a golf ball in the shape of a sphere.

[ Mar. 12, 1974 United States Patent Dale Primar y ExahzinerGeorge J. Marlo 1 GOLF PUTTING PRACTICE DEVICE [76] Inventor: James Thomas Dale, 71-973 San Attorney Agent Firim'*Thomas Jacinto Dr., Rancho Mirage, Calif. 92270 22 Filed: Sept. 7, 1972 21 Appl. No.1 287,055

CH 3 8 1 3 7 2 1 C Sh Um N 1 55 [I ter and axially distributed near the central portion of 58 Field ofSearch 273/128 199, 183, 213,

the device. The object is to provide an exaggerated 273/200 off-target directional motion of the device when it is struck by a golf putter club at 'an improper angle.

References Cited UNITED STATES PATENTS 7/1884 12/1902 Lightweight spherical dimpled elements may be attached to opposite sides of the device to produce the appearance of a golf ball in the shape of a sphere.

Haskell OTHER PUBLICATIONS GolfDigest, June 1970, page 112, No. 6. 1

Fisher 2 Claims, 4 Drawing Figures Volume 21 PAIENTED "AR 1 2 I974 a j haw GOLF PUTTING PRACTICE DEVICE In the game of golf, the-last stroke or two at the end of each hole is commonly known as a putt. It is an ob ject of this invention to provide a device which will enable a golfer to determine the accuracy of the striking attitude of the golf club against a surface which simulates a golf ball surface. It is a further object to construct such a device which responds rapidly in such a manner that inaccuracy in striking the ball is obvious to the golfer.

Another object is to construct a practice putting device with the same weight and feel" to a putting stroke as a standard golf ball.

The novel features that are considered characteristic of this invention itself will best be understood from the following description when read in connection with the accompaning drawings, in which:

F IG. 1 is a perspective view of one example of the invention; FIG. 2 is a side elevation view; FIG. 3 is a schematic drawing showing a stroking surface contacting the rounded surface of putter practice device tangentiallyadn the path taken by the device in reaction; and FIG. 4 is a schematic drawing showing a stroking surface contacting the rounded surface of the putter prac tice device at an angle from a tangent to the curved surface of the device.

In FIG. I, the outer curved surface defines a symmetrical segment of a sphere in which curved surface 1 is exactly equal in curvature and spherical diameter to an equivalent segment from a standard golf ball. The width of the segment is approximately 0.66 inches measured along an edge to edge chord of the segment. The

surface contains symmetrical pitted areas identical to 3 to an inner rim 4. The depth of the undercut is about 0.15 inch on each side of the device, for a purpose to be described later. Inner rim 4 defines the outer edge of a collar 5 which confines a relatively heavy cylindrical mass 6 which is preferably made from lead. Mass 6 is about 0.5 inches in diameter and about 0.66inches in length, and preferably the same length as the width of the cylindrical segment. Such a lead mass weighs about L2 ounces. The materials of the device, excluding the mass 6 is of a plastic material or hard rubber which simulates the appearance and feel of a standard golf ball. The weight of the plastic is about 0.42 ounces, therefore, approximately 75 percent of the weight of the putting device, which totals 1.62 ounces, is concentrated in the 0.5 inch central mass 6. The total weight is within the tolerances of a standard golf ball as approved by the United States Golfing Association. As previously mentioned, the putting device is undercut between edge 3 and inner rim 4. The reduction of mass between collar 5 and outer rim 2 assists in concentrating the mass toward the center of the putting device.

In FIG. 3, a portion of a putter club 7 is' shown with surface 8 which strikes the ball. If striking surface 8 moves along a path indicated by arrows 10, which path is perpendicular to surface 8 and which contacts the putting device in the center of curved surface 9, then the putting device reacts. by moving in the intended path shown by arrows l1.

In FIG. 4, the putter club 7 is shown with surface 8 inclined at an angle from the perpendicular path of FIG. 3. For purposes of illustration, the angle is much exaggerated. It has been found that even a I" inclination of the striking face of the putter causes a substantial deviation in the direction traveled by the putting device. The concentration of mass at the center of the putting device increases the effect of any errors in striking the surface of the putting device. High speed photographs show that for several feet after the putter device has been struck at even avery slight angle, the device oscillates about a vertical axis, then the rotation is stabilized andthe device continues rolling.without oscillation, in a direction away from the intended path. The initial oscillation is presumably causedbythe dynamic unbalance of the putting device as it rotates around an unsymmetrical axial plane.

In both FIG. 1 and FIG. 2, it is readily noticeable that the putting device resembles a wheel. It has been found that a light weight decorative cover (not shown) can be inserted in the wheel to conceal the undercut area, collar 5, and mass 6. The cover is installed on both sides of the putting device to provide a more pleasing appearance, as well as offering an area on which design or advertising can be displayed. 5

Having now described my invention, I claim:

1. A device for improving the putting ability of a golfer comprising, wheel-shaped means having approximately the same weight, diameter, and dimpled surface characteristic as a standard golf ball, and a cylindrical relatively heavy mass in the hub of said wheelshaped means, said mass having about percent of the weight of said device and having a diameteer of about 0.5 inches.

2. A device in accordance with claim 1 in which opposite sides thereof are covered with a lightweight, parapperance of a standard golf ball. 

1. A device for improving the putting ability of a golfer comprising, wheel-shaped means having approximately the same weight, diameter, and dimpled surface characteristic as a standard golf ball, and a cylindrical relatively heavy mass in the hub of said wheel-shaped means, said mass having about 75 percent of the weight of said device and having a diameteer of about 0.5 inches.
 2. A device in accordance with claim 1 in which opposite sides thereof are covered with a lightweight, partially spherical dimpled material which produces the apperance of a standard golf ball. 